## mathsux4real Group Title Please help :0 Find the term containing x^42 of (x^3-3)^16 2 years ago 2 years ago

1. satellite73

well first we need $$\frac{42}{3}=14$$ to know which term we want

2. satellite73

so it is either the 14th term or the second term depending on how you are counting. makes no difference. the term looks like $\dbinom{16}{2}(x^3)^{14}(-3)^2$

3. satellite73

$\dbinom{16}{2}=\frac{16\times 15}{2}=8\times 15=120$ and $$(-3)^2=9$$ multiply to get your answer